With continuous development of internet technologies, at present, products based on various cloud architectures emerge one after another. A carrier of cloud storage technologies is a cloud system. Specifically, the cloud system includes a public cloud and a private cloud. The private cloud is safe, but is not easy to be called on a large scale. The safety of the public cloud seems to be somewhat poor from both an actual application view and a psychological point of view, however, various computing resources, storage resources and bandwidth resources of the public cloud are much better. Therefore, many users are in a dilemma of facing security problems while storing their data in a public network.
For example, nowadays, a lot of data, such as audios, videos, texts, e-mails and pictures, are private data of individuals or public institutions. If such data are only stored at one service provider, no matter how the provider provide encryption, users will always consider that the data are out of their own control, which will make the users feel unsafe. Currently, the main technology used in the world encrypts, with its own encryption means, the users' data to be saved, and then stores such data.
It can be predicted that desired plain text can be acquired from data stored in a cloud system or other storage systems, by acquiring an encryption password or reversely calculating a decryption password with a Maxotek Breaker Ultimate, so as to directly read the plain text. A data block is used as a main carrier of data. If file content of the data block is maliciously acquired, it is prone to leaks. Thus, there is a need for a method to solve the security problem of the data block in a cloud storage environment.